Infallibility (Arabic: ʿIṣma [العِصمَة]) means abstinence from sins and from disobedience to God. The belief in the infallibility of the Prophets and Imams, from intentional or unintentional sins , is a part of Shi'a creed. Most of the scholars and thinkers have pointed to the existence of general capability and freewill for abstinence from sins in the infallible person.

To explain the origin of infallibility, several opinions have been put forth, such as: the four means of divine benevolence, knowledge and awareness of the consequences of sins, freewill and choice, knowledge and a combination of natural, personal, and divine elements.

The discussion about the infallibility of the prophets expands to different degrees and levels and in each level various debates have taken place among thinkers and theologians. These discussions range from immunity from polytheism (Shirk) and disbelief (Kufr) to immunity from normal mistakes.

Since Imam is the successor of the Prophet (s) and the authoritative source of religious knowledge, including practical laws, spiritual teachings of the religion, exegeses of the Qur'an and Sunna of the Prophet (s), he must be immune from mistakes or sins so that people can trust him and his words. Otherwise, people would lose their trust in him and God's purpose in appointing an Imam for guidance will not be fulfilled. The infallibility of the Imams includes two main areas: Practice and Knowledge.Read more...